<!-- Collection of code snippets by Arne Vajhøj -->
<!-- posted to eksperten.dk, usenet and other places (2002-now) -->
<?php
$doc = new DOMDocument();
$doc->load('C:\before.xml');
$sounds = $doc->getElementsByTagName('sound');
foreach($sounds as $sound) {
    $sound->parentNode->removeChild($sound);
}
$doc->save('C:\after.xml');
?>